dcons(4freebsd)

dcons4freebsd

Dumb console device driver

Usage

To compile this driver into the kernel, place the following lines in your kernel configuration file:

options GDB device firewire device dcons

Alternatively, to load the driver as a module at boot time, place the following line in your kernel configuration file:

options GDB

and in loader.conf(5):

dcons_load="YES"

Overview

The dcons device is a simple console device which just reads from and writes to an allocated buffer for input and output respectively. It is of no use by itself and it is supposed that the buffer is accessed via a bus like firewire(4) or kvm(3) for interaction.

The buffer consists of 4 channels. There are 2 ports, one for the console TTY and another is GDB port, then each port has an input channel and an output channel.

Files

/dev/dcons
/etc/ttys

Examples

If you want to run getty(8) on dcons, insert the following line into ttys(5) and send a HUP signal to init(8) using kill(1).

dcons	"/usr/libexec/getty std.9600"	vt100	on  secure

Once the fwohci(4) device is initialized to allow physical access, the buffer can be accessed from another host via a firewire(4) bus using the dconschat(8) application. See dconschat(8) for more details.

If you want to use dcons as a gdb(1) port, add the following line into loader.conf(5):

dcons_gdb="1"

Releases

9 releases since Debian 5.0 (Lenny); the text changed 6 times.

  1. 5.0
  2. 6.0
  3. 7
  4. 8
  5. 9
  6. 10
  7. 11–13

Authors

Hidetoshi Shimokawa ⟨[email protected]⟩

Bugs

This driver is currently under development.

From freebsd-manpages 12.2-2 in Debian 13 (Trixie). Parsed by carta from the page's mdoc source.